19-1489; Rev 0; 12/00
GSM Cellular/PCN Handset RF Power
Management IC
General Description
Features
The MAX1727 is a radio frequency (RF) power-man-
agement IC intended for Global Satellite Mobile (GSM)
communication cellular and personal cellular network
(PCN) handsets using a single lithium-ion (Li+) cell bat-
tery with inputs from +3.1V to +5.5V. The IC contains
four low-noise, low-dropout (LDO) linear regulators to
provide all the supply voltage requirements for the RF
portion of the handset, and two high-speed, wide-band-
width op amps for the power amplifier (PA) power con-
trol loop.
ꢀ +3.1V to +5.5V Input Range
ꢀ One 2.90V, 100mA Low IQ LDO
ꢀ One 2.75V, 50mA Low IQ LDO
ꢀ One 2.75V, 20mA Low IQ LDO
ꢀ Low-Noise LDOs
<90µV
from 10Hz to 100kHz
RMS
>80dB Crosstalk Isolation at 10kHz
>70dB PSRR at 1kHz
Each LDO has its own individual on/off control to maxi-
mize design flexibility. All LDOs are internally trimmed
to a fixed output voltage and are optimized for low
noise and high crosstalk isolation. LDO1 (R1OUT) is
rated for 100µA and is optimized for lowest quiescent
current. It is intended to power the transmitter, receiver,
and synthesizer. LDO2 (R2OUT) is rated for 50mA. It is
intended to power the TCXO, GSM, and PCN high-
power voltage-controlled oscillators (VCOs). LDO3
(R3OUT) is rated for 20mA and is optimized to sup-
press line transients. It is intended to power the UHF
offset VCO. LDO3 has an auxiliary 2.5Ω switched out-
put to allow the VCO to be powered up with precise
timing. LDO4 (R3BYP) is rated for 20mA. It is intended
to power this IC’s reference and LDO3 for superior line
rejection. LDO4 and the reference will be powered on if
any of the R1EN, R2EN, and R3EN enable inputs are
logic high.
ꢀ
5ꢀ Aꢁꢁuraꢁc Oꢂer Line, Load, and ꢃemperature
ꢀ ꢃhree 2.5Ω Switꢁhed Outputs
ꢀ Current and ꢃhermal Limit
ꢀ ꢃwo Undediꢁated Op Amps
Rail-to-Rail CMR Inputs and Outputs
>120dB Channel Separation
>85dB PSRR at 1kHz
ꢀ 10µA (max) Shutdown Current
Ordering Information
PARꢃ
ꢃEMP. RANGE
PIN-PACKAGE
MAX1727EUG
-40°C to +85°C
24 TSSOP
The op amps have wide bandwidth, high DC accuracy,
high slew rate, and Rail-to-Rail® inputs and outputs.
The op amps can sink and source 3mA, and include
two 2.5Ω switched outputs. The op amps and switched
outputs may be used independently or may be config-
ured to provide optimized power for a PA control loop.
Pin Configuration
R3EN
PCEN
1
2
3
4
5
6
7
8
9
24 GND
23 CBYP
22 ENVCO
21 VCOOUT
20 R3OUT
19 R3BYP
PC1+
Applications
PC1-
PC1OUT
GSM Cellular or PCN Handsets
Single-Cell Li+ Systems
V
PC
MAX1727
PC2OUT
PC2-
18 R1OUT
17
3-Cell NiMH, NiCD, or Alkaline Systems
V
CC
PC2+
16 R2OUT
15 R2EN
PCNAPC 10
Typical Application Circuit and Functional Diagram appear
at end of data sheet.
BANDSWIN 11
GSMAPC 12
14 R1EN
13 GSM/PCN
ꢃSSOP
Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd.
________________________________________________________________ Maxim Integrated Products
1
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